Compressing unit



. y 1935- E. HEITMAN 2,001,874

COMPRESSING UNIT Filed Oct. 12, 1951 IN VEN TOR.

EDWfl/ED H51 TMHN mgumm A TTORNEY.

Patented May 21, 1935 PATENT OFFICE COMPRESSING UNIT Edward Heitrnan, Detroit, Mich, assignor to Keivinator Corporation, Detroit, Mich., a corporation of Michigan Application October 12, 1931, Serial No. 568,319

1 Claim.

5 for other service of a similar character.

Some of the objects of the invention are to provide a refrigeration apparatus of this type which will be relatively quiet and efllcient in operation'and in which oil pumping, prevalent to a greater or less degree in refrigeration units of this character, heretofore employed, will be substantially decreased.

' The invention generally embraces a refrigerant condensing'unit in which'the compressor is provided with suction and discharge valves in the head of the cylinder thereof and in which the suction line communicates with both the suc-' tion valve and the crank case of the compressor through a passage formed in the compressor wall. compressor is in a direction such that. the oil adhering to the crank will be thrown elsewhere than into the passage connecting the crank case with the head of the compressor.

For a better understanding of the invention reference may now be had to the accompanying drawing forming a part of this specification, in

which: I

Figure 1 is a side elevational view of a refrigerant condensing unit embracing the invention and in which figure a portion of the refrigerant compressor is broken away to illustrate the interior construction thereof;

Figure 2 is a fragmentary cross sectional view on an enlarged scale of an upper portion of 'the compressor illustrated by Figure 1; I

Figure 3 is a fragmentary cross sectional view of the refrigerant compressor head taken substantially on line 3-3 thereof. I

Figure 4 is a fragmentary view of arefrigerator embracing a refrigerant evaporating unit for cooling the interior thereof.

Referring more in detail to the refrigerating mechanism illustrated by the drawing, a refrigerator l embracing insulated walls II and i2 is provided with an evaporating unit l3 in which liquid refrigerant is vaporized and in'being so vaporized absorbs the heat which is conducted through the walls of the refrigerator. The evaporating unit consists principally of a float chamber I4 containing a conventional lowside float, not shown, from which extends a plurality of refrigerant circulating conduits i5 joined at their outer extremities and to which are attached a plurality of vertically disposed heat conducting The rotation of the crank shaft of the fins l6. Liquid refrigerant is supplied to the evaporating unit l3 through a liquid line l1 and vaporized refrigerant is exhausted through a suction conduit IS. The liquid line 11 is connected to a lower portion of a liquid receiver is which 5' forms an element of a refrigerant condensing unit 2|. The suction line It communicates at its opposite end with a suction line out off valve 22 attached to and communicating with the suction side of a refrigerant compressor 23. Bolts 24 projecting through a flange 25 formed on the lower extremity of the compressor 23 serve the purpose of securing the compressor rigidly to a condensing unit base 26.

The compressor is driven by a motor 21, secured to the base 26 by brackets and bolts indicated at 28, through a belt 29 which engages a drive pulley 3| of the motor and a combination driven pulley and fly wheel 32 attached to the compressor. The motor 21 also drives a fan 33 which is adapted to discharge a blast of air upon a vertically disposed refrigerant condenser 35 likewise supported, by the base 26 and secured rigidly to the latter upon a bracket 36 extending therefrom. One end of the condenser 35 communicates, through a conduit 31, with an outlet coupling 38 from a cavity 39 formed in the interior of a head 4| of the compressor 23. An inlet coupling 42 associated with an opposite portion of the cavity communicates with one end v3t) of a conduit 43 which in turn is connected at its opposite end to a discharge cut of! valve 44 communicating with the high side of the compressor 23. The opposite end of the condenser 33 communicates through a condui not shown, with an upper portion of the ref gerant receiver 39.

It will be apparent from the description of this structure that compressedrefrigerant vapor discharged from the compressor 23 through the conduit 43 will pass first through the cavity 3! in the head 4! and then through the conduit 31 a to an upper portion of the condenser 33. Liquefled refrigerant formed in the condenser 33 is discharged therefrom into the receiver from whence it is in turn conducted through the liquid 45 line 11 to the evaporating unit 13. g i

The compressor 23 comprises a crank case 48 having bearings formed at opposite ends thereof in which a crank shaft 41 is journalled. Connecting rods 48 and 49 journalled respectively on 50 the two throws 5| and 52 of the crank shaft 41 are adapted to reciprocate pistons 53 and 54 of I the two cylinders 56 and 51 of the compressor. Both of. the cylinders 58 and 31 are cast as a unit with thecrank case 48. The upper ex- 6!} tremities of the cylinder are covered'by a plate dt through which a plurality of inlet openings 5% and an exhaust opening iii are formed for each cylinder. The upper surface of the plate 58 is in turn covered by a valve plate 62 with which discharge valves 63 and inlet valves 65 for each of the cylinders are associated. The inlet valves 54%, which are arranged on the lower side of the valve plate 52 in recesses 56 formed in the upper surfaces of the plates so, comprise relatively flat reeds fil which cover orifices 58 formed in the plate 52, and slightly curved reeds es positioned immediately beyond the fiat reeds and abutting the latter at opposite extremities thereof. Such abutting ends of the reeds 6i and 69 are provided with aligned openings through which pins ii project; the opposite ends of the pins being disposed in openings formed in the adjacent surfaces of the plates 58 and 62.

During the normal operation of the compressor 23, the reeds ti merely curve slightly away from the orifices 68 to permit the entrance of refrigerant vapor to the cylinders on the suction stroke of either of the pistons, butin the event a greater flowof gas is required through the orifices t8, the curved reeds 69 will be somewhat strai htened thus permitting the reed iii to move farther away from the seating surfaces therefor. The orifices 638 each communicate with a horizontally arranged passage 72 which is formed partly in the upper surface of the valve plate 62 and in the lower surface of the cylinder head ii. Adjacent the opposite extremities of this passage and directly above the cylinders 5'5 and 5'5 are formed cavities it which are provided for the purpose of permitting the use of valves other than the type herein illustrated.

A central portion of the passage 12 communicates withthe upper extremity of a vertically disposed duct ill formedthrough the plates 62 and 58, and an upper portion of a compressor cylinder block it embracing the cylinders 55 and 57. This duct, which is arranged in the block it at one side of but midway between the cylinders 5t and 5i, communicates at its lower extremity with a cored chamber ll formed in the cylinder block immediately above the crank case it and communicating with the latter through an opening it. One side of this chamber is provided with an inlet opening '59 which communicates with the suction line is through the suction line out off valve 22.

A reduction in pressure in the cylinders and 5'5, caused by the reciprocation of the pistons 58 and 5 5 and the operation of the valves 64, iiiitiates a flow of gas from the suction line it, through the opening 19 into the chamber ,ll, through the duct it in the passagelZ and into the cylinders through the orifices $8 at the opposite ends of the passage 72 andthe openings 59 beneath the suction valves 64. The reciprocation of the pistons 53 and 56 also tends to cause variations in pressure in the crank case i6 which are compens'ated for by the intermittent flow of gas between the chamber ll and the crank case 416 through the "opening it.

The rotation of the crank shaft W is such that when it'emerges from the oil contained in the crank case 63 the oil adhering to the throws of acetate crank case opposite that i rich the opening it; leading to the chamber it is formed. In other words, the throws of the crank will move downwardly on the side of the crank case containing valves 66 in that each comprises a relatively 1 straight reed 83 which is in position by a curved plate or stop 8%, the opposite ends of both the reeds and stops being provided with openings through which project studs tit secured in openings in the valve plate 62 on opposite sides of the ports 82. Coil springs 87 are positioned between the heads of the studs 86 and the ends of the stops for the purpose of holding the latter resiliently against the ends of the reeds. passage iii communicates with. the discharge cut off valve il communicating with the discharge line it from the compressor.

When, by reason of the reciprocation. of the pistons 53 and 54% and the operation of the valves of the compressor, the pressure in the cyiinders 5t and 5? is increased a predetermi compressed gas will be fGif-C to be observed that the pistons 53 and 541 are without the usual inlet valves therein and that the oil saturated gas passes not through the pistons as in ordinary refrigerant compressors but enters the head of the compressor through separate passage and then is admitted to the cylinders through inlet valves positioned thereabove.

While only a preferred form of the invention is illustrated and described in detail herein, it is apparent other structures may be de' vised embracing the principles of the invention within the scope of the appended claim.

I claim:

A refrigerant compressing unit comprising a compressor having a crankcase and including a cylinder disposed above the crankcase, a valve plate arranged to close the top of the cylinder, a piston reciorocable in the cylinder, an inlet valve carried by said plate, a wall for compressor having a passage formed therein and an inlet leading to said passage, said passage at opposite ends being in communication with the inlet valve and the crankcase, respectively, and

An intermediate portion of the. 

